Recording devices such as printers, copying machines, and facsimile machines, are used to record information on recording media such as paper by means of recording materials such as ink. A recording device comprises a body, and an ink cartridge mounted detachably in the recording device. To ensure that the recording device is able to detect fitness of the ink cartridge within it, the ink cartridge is usually provided with a chip mounted detachably on the ink cartridge. The chip comprises a storage unit, for storing related information about the ink cartridge. When the ink cartridge is arranged on the recording device, the chip of the ink cartridge is electrically connected to the recording device, and exchanges data with the body of the recording device. Specifically, the chip of the ink cartridge is electrically connected to the body of the recording device through terminals, each of the terminals being connected to the storage unit of the chip.
Since the chip comprises at least two terminals electrically connected to the recording device, and there is a potential difference between these terminals while the chip is being used, there might be liquid or dust falling between the two terminals having a potential difference therebetween, for example, between a power supply terminal and a ground terminal, thereby leading to a short circuit and causing damage to the storage unit.
In addition, besides the storage unit, the ink cartridge is also provided with other devices such as a high-voltage circuit with a voltage higher than the driving voltage of the storage unit, a piezoelectric sensor or an induction coil, a resistor, etc. In this case, short circuits will probably occur between terminals of one of the devices and terminals of another device, thus potentially damaging the ink cartridge or the recording device.
Therefore, in order to prevent the ink cartridge or the recording device from being damaged, it may be necessary to detect occurrence of the above-said short circuit in advance.
According to an existing technology of detecting short circuit of chips, the recording device is provided with a short-circuit detection circuit, which judges presence of a short circuit between terminals of the chip by detecting a voltage change on a device-side terminal. However, said detection is performed after the ink cartridge has finished the installation detection on the recording device, at which time, the short circuit is detected, but the storage unit might have been damaged, thus rendering the ink cartridge unusable. Moreover, the above short-circuit detection circuit is provided on the recording device, and therefore, for those recording devices that have already been in the market and are not provided with a short-circuit detection circuit, there will still be difficulties in detecting the short circuit timely, thereby damaging the ink cartridge or the recording device.
According to another existing technology of detecting short circuit of chips, the chip is provided with a battery and a short-circuit detection circuit. The battery supplies power to the short-circuit detection circuit so that short circuit detection of the chip can be performed. After the ink cartridge is arranged in the recording device, the chip is electrically connected to the recording device. Presence of a short circuit between terminals is thus judged by detecting a voltage change on a short-circuit detection terminal of the chip, or by detecting a signal change between the short-circuit detection terminal and a terminal to be detected of the chip. However, according to this existing technology, the short circuit detection can only be performed by providing the chip with a battery, which will increase the manufacturing cost of the chips, and will give rise to the problem that the short circuit detection cannot be performed when the battery runs out after a long-term use.